338 EUROPE: A GEOGRAPHICAL SURVEY developed system of schools and colleges has almost eliminated illiteracy, and has aided materially in increasing the ability of the population. Few people throughout the world have so successfully adjusted them- selves to their environment as have the Danes. The Occupations of the Population.—Agriculture is the princi- pal activity of Denmark, as is shown by the fact that 34.8 per cent of the working population is engaged in that occupation, while 27 per cent is engaged in manufacturing and 16.7 per cent in commerce and trans- portation. Even these statistics do not present a true picture of the importance of agriculture, for most of the manufacturing is concerned with the preparation of agricultural raw materials. Commerce and transportation have always been important, and they remain so, as is shown by the relatively large proportion of the population engaged in those activities. SITUATION Denmark occupies a portion of the Jutland Peninsula and some 350 islands, only 100 of which are inhabited. It is really an arm of the great European plain, reaching out toward the Scandinavian Peninsula and almost blocking the entrance to the Baltic. The Skagerrak sepa- rates the peninsula from Norway, and the Kattegat separates its north- ern section from Sweden. South of the Kattegat the entrance to the Baltic is blocked by a number of islands, the largest of which are Fyn and Sjaelland. The former is separated from the peninsula by a narrow • body of water known as the Little Belt, and from the latter by the Great Belt. Sjaelland in turn is separated from the Swedish coast by the Sound, a body of water which is only three miles wide at its narrowest point. The possession of the peninsula and these islands thus gives Denmark control of the natural entrances to the Baltic. Not until the construction of the Kiel Canal was it possible to enter or leave the Baltic without passing through Danish waters. It was this fact that enabled Denmark to collect tolls for entry to the Baltic, a practice which it inherited from the Hanseatic period and continued until 1857. These tolls were collected at the old toll city of Helsingor on the northern or narrowest portion of the Sound. It was also responsible for the fact that Kobenhavn, on the southern or widest portion of the Sound, became a great distributing center for the Baltic territories. This is a natural point for the transshipment of goods entering or leaving the Baltic. As long as this sea was the most important body of water in northern Europe, Denmark occupied a most